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Large-scale inhomogeneities in modified Chaplygin gas cosmologies

Luis P. Chimento·Ruth Lazkoz
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Abstract

We extend the homogeneous modified Chaplygin cosmologies to large-scale perturbations by formulating a Zeldovich-like approximation. We show that the model interpolates between an epoch with a soft equation of state and a de Sitter phase, and that in the intermediate regime its matter content is simply the sum of dust and a cosmological constant. We then study how the large-scale inhomogeneities evolve and compare the results with cold dark matter (CDM), $Λ$CDM and generalized Chaplygin scenarios. Interestingly, we find that unlike the latter, our models do always resemble $Λ$CDM.

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Luis P. Chimento, Ruth Lazkoz. 2005-05-18. Large-scale inhomogeneities in modified Chaplygin gas cosmologies. https://doi.org/10.1016/j.physletb.2005.04.029

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